From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jan Kiszka <jan.kiszka@siemens.com>
Subject: Re: KVM: x86: Push potential exception error code on task switches
Date: Wed, 14 Apr 2010 14:37:18 +0200
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Cc: Marcelo Tosatti <mtosatti@redhat.com>, kvm <kvm@vger.kernel.org>,
	Gleb Natapov <gleb@redhat.com>
To: Avi Kivity <avi@redhat.com>
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Avi Kivity wrote:
> On 04/14/2010 03:11 PM, Jan Kiszka wrote:
>> When a fault triggers a task switch, the error code, if it exists, has
>> to be pushed on the new task's stack. Implement the missing bits.
>>
>>
>> @@ -2416,12 +2417,23 @@ static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
>>   	ops->set_cached_descriptor(&next_tss_desc, VCPU_SREG_TR, ctxt->vcpu);
>>   	ops->set_segment_selector(tss_selector, VCPU_SREG_TR, ctxt->vcpu);
>>
>> +	if (ret == X86EMUL_CONTINUE&&  has_error_code) {
>> +		struct decode_cache *c =&ctxt->decode;
>> +
>> +		c->op_bytes = c->ad_bytes = (next_tss_desc.type&  8) ? 4 : 2;
>>    
> 
> Don't these depend on the attributes of the segment as well?

Not on the segment, but actually on the gate size. Will fix.

Jan

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